Vladimir S. Komlev

A. A. Baikov Institute of Metallurgy and Materials Science (IMET)

Biocompatible calcium phosphate ceramic grafts are able of supporting new bone formation in appropriate environment. The major limitation of these materials usage for medical implants is the absence of accessible methods for their patient-specific fabrication. 3D printing methodology is an excellent approach to overcome the limitation supporting ef...

Bioceramics are used to treat bone defects but in general do not induce formation of new bone, which is essential for regeneration process. Many aspects related to bioceramics synthesis, properties and biological response that are still unknown and, there is a great need for further development. In the most recent research efforts were aimed on cre...

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The use of platelet rich plasma (PRP) in bone repair remains highly controversial. In this work, we evaluated the effect of lyophilized PRP on bone regeneration when associated with a silicon stabilized hydroxyapatite tricalcium phosphate scaffold in a rabbit calvarial defect (Skelite™). Critical defects were created in the calvaria of twenty-four...

The development of an in vitro model of bone and the optimization of tools for determining the biological processes occurring during bone repair remains a major goal in the field of bone tissue engineering. Recently, a model based on a three-dimensional co-culture of osteoblasts and osteoclast precursors in Skelite(TM) scaffolds was developed. Alth...

Space exploration is perhaps one of the most difficult tasks ever undertaken since the emergence of humankind. The International Space Station is a unique platform for advanced technology research that is not possible anywhere else. Tissue engineering in outer space, where state of the gravity can be 'turned off' or 'turned on' in the case of appli...

Zirconia-toughened alumina (ZTA) powders with 20.0 wt.% of ZrO2 were synthesized using the coprecipitation method. Transmission electron microscopy indicated that the powders contained needle-like particles 15–30 nm long and 50–70 nm flake-like particles with a uniform component distribution. Effects of different Y2O3 concentrations (3.0, 4.0, or 5...

Методами импульсного электронного парамагнитного резонанса проведена характеризация синтетических гидроксиапатитов, легированных редкоземельными ионами (гадолиний и церий). Обнаружено, что ионы гадолиния и церия успешно встраиваются в кристаллическую решетку гидроксиапатита в предлагаемом методе синтеза (влажное осаждение), занимая позицию ионов ка...

One of the key factors of the interaction ‘osteoplastic material—organism’ is the state of the implant surface. Taking into account the fact that the equilibrium in regeneration conditions is reached only after the reparative histogenesis process is completed, the implant surface is constantly modified. This work is devoted to the numerical descrip...

The creation of injectable bone cements (BC) remains a pressing issue in modern biomaterial science due to the prospects for their use in minimally invasive surgical interventions in onco-orthopedics for replacing bone defects in patients that occur after removal of primary or metastatic spinal tumors.

This article discusses the application of computational methods using density functional theory (DFT) to construct models of the nitrogen impurity center in octacalcium phosphate (OCP). The performed DFT calculations are compared with the electron paramagnetic resonance spectra (g-factor and the hyperfine interaction constant A). It is shown that i...

Mesoporous hydroxyapatite (HA) is widely used in various applications, such as the biomedical field, as a catalytic, as a sensor, and many others. The aim of this work was to obtain HA powders by means of chemical precipitation in a medium containing a polymer—polyvinyl alcohol or polyvinylpyrrolidone (PVP)—with concentrations ranging from 0 to 10%...

A comparative study of gelation processes in aqueous solutions of sodium alginate initiated by their chemical crosslinking with divalent Ca 2+ or Ba 2+ ions is carried out. 3D cryoprinted hydrogel scaffolds with certain architectonics are formed from the studied compositions containing various concentrations of cross-linking agents. It is shown tha...

The structure of hydroxyapatite (HA) plasma coatings obtained during changing of the power of a plasma torch (P) from 20 to 26 kW has been studied using X-ray diffraction analysis. All coatings contained the products of hydroxyapatite decomposition in the plasma flow, phases of tetracalcium phosphate (TTCP), and CaO. The increase in their contents...

Calcium sulfate powder materials containing terbium ions at 0, 1.0, or 2.0 mol.% were obtained. They are characterized by the presence of a CaSO4 × 0.5H2O phase, while Tb3+ is incorporated into the lattice at ≤1.0 mol.%. Specific surface area enlarged from 2.1 to 22.5 m2/g as crystallite size decreased from 68 to 31 nm. Thermal analysis showed that...

Hydroxyapatite (HA) remains one of the most popular materials for various biomedical applications and its fields of application have been expanding. Lithium (Li⁺) is a promising candidate for modifying the biological behavior of HA. Li⁺ is present in trace amounts in the human body as an alkaline and bioelectric material. At the same time, the intr...

Creating bioactive materials for bone tissue regeneration and augmentation remains a pertinent challenge. One of the most promising and rapidly advancing approaches involves the use of low-temperature ceramics that closely mimic the natural composition of the extracellular matrix of native bone tissue, such as Hydroxyapatite (HAp) and its phase pre...

Hydroxyapatite (HAp)-based materials doped with rare earth elements (REE) have shown applications as biomaterials, lighting emitting materials, scintillating materials, in vivo imaging probes, and thermoluminescent dosimeters. Gadolinium-containing calcium phosphates are promising contrast agents for various bioimaging modalities. In this work, hyd...

This study examined the effectiveness of coating demineralized bone matrix (DBM) with amorphous calcium phosphate (DBM + CaP), as well as a composite of DBM, calcium phosphate, and serum albumin (DBM + CaP + BSA). The intact structure of DBM promotes the transformation of amorphous calcium phosphate (CaP) into dicalcium phosphate dihydrate (DCPD) w...

Calcium sulfate (CS) materials containing terbium ions at 0, 1.0, or 2.0 mol.% were obtained by mechanochemical synthesis. According to X-ray diffraction data, the powder materials are characterized by the presence of a CaSO4×0.5H2O phase, while Tb3+ is incorporated into the lattice at ≤1.0 mol.%. Specific surface area enlarged from 2.1 to 22.5 m2/...

In the present study, the efficiency of a biomimetic approach by coating demineralized bone matrix (DBM) amorphous calcium phosphate (DBM+CaP), including its combination with serum albumin (DBM+CaP+BSA), was investigated. The intact structure of DBM promotes the transformation of amorphous calcium phosphate (CaP) into DPCD with a characteristic pla...

α-tricalcium (α-TCP) phosphate is widely used as an osteoinductive biocompatible material, serving as an alternative to synthetic porous bone materials. The objective of this study is to obtain a highly filled fibrous nonwoven material composed of poly-3-hydroxybutyrate (PHB) and α-TCP and to investigate the morphology, structure, and properties of...

Bones are the fourth most frequent site of metastasis from malignant tumors, including breast cancer, prostate cancer, melanoma, etc. The bioavailability of bone tissue for chemotherapy drugs is extremely low. This requires a search for new approaches of targeted drug delivery to the tumor growth zone after surgery treatment. The aim of this work w...

The development of magnesium calcium phosphate bone cements (MCPCs) has garnered substantial attention. MCPCs are bioactive and biodegradable and have appropriate mechanical and antimicrobial properties for use in reconstructive surgery. In this study, the cement powders based on a (Ca + Mg)/P = 2 system doped with Zn2+ at 0.5 and 1.0 wt.% were obt...

The injectable hydrated calcium phosphate bone-like paste (hCPP) was developed with suitable rheological characteristics, enabling unhindered injection through standard 23G needles. In vitro assays showed the cytocompatibility of hCPP with mesenchymal embryonic C3H10T1/2 cell cultures. The hCPP was composed of aggregated micro-sized particles with...

The development of magnesium calcium phosphate bone cements (MCPCs) have garnered big attention. MCPCs are bioactive and biodegradable and have appropriate mechanical and antimicrobial properties for use in reconstructive surgery. In this study, the cement powders based on a (Ca + Mg)/P = 2 system doped with Zn2+ at 0.5 and 1.0 wt.% were obtained a...

The injectable hydrated calcium phosphate bone-like paste (hCPP) have been developed with suitable nanoscale characteristics and unindered injection through 23G standard needles. In vitro assays showed the cytocompatibility of hCPP with mesenchymal embryonic C3H10T1/2 cell cultures. The hCPPs were identified to be composed of aggregated nano-sized...

Natural and synthetic hydrogel scaffolds containing bioactive components are increasingly used in solving various tissue engineering problems. The encapsulation of DNA-encoding osteogenic growth factors with transfecting agents (e.g., polyplexes) into such scaffold structures is one of the promising approaches to delivering the corresponding genes...

Space exploration is perhaps one of the most difficult tasks ever undertaken since the existence of mankind. International Space Station (ISS) is a unique instrument for advanced technology research that is not possible anywhere else. Tissue engineering in a space environment where “turnoff” gravity can be done is the most emerging field with high-...

Методом осаждения из растворов получены наноразмерные порошки церийсодержащих трикальцийфосфатов (ТКФ, Ca3(PO4)2) со структурой витлокита. Содержание церия в материалах после термической обработки при 1300°C составило 0, 0.07, 0.18 и 0.39 мас. %, что соответствует значениям х = 0, 0.0025, 0.006, 0.013 для общей формулы Ca3-хCe2х/3(PO4)2. С повышени...

В работе исследованы цементные материалы на основе сульфата кальция (СК), содержащие до 5 мол. % катионов лития. Установлено, что присутствие ионов лития увеличивает растворимость СК-цементов в растворе Дульбекко, при этом значение рН вытяжек изменяется с 6.0 до 8.7. Катионы лития определяются в фосфатно-буферном растворе Дульбекко на первые сутки...

Bone grafts with a high potential for osseointegration, capable of providing a complete and effective regeneration of bone tissue, remain an urgent and unresolved issue. The presented work proposes an approach to develop composite biomimetic bone material for reconstructive surgery by deposition (remineralization) on the surface of high-purity, dem...

Powders based on β-tricalcium phosphate (β-TCP) containing sulphate groups at up to 12.0 mol.% were synthesised by chemical precipitation from aqueous solutions. The obtained materials were characterised by X-ray phase analysis, Fourier transform infrared spectroscopy, measurement of specific surface area, scanning electron microscopy, energy dispe...

Mesoporous hydroxyapatite (HA) materials demonstrate advantages as catalysts and as support systems for catalysis, as adsorbent materials for removing contamination from soil and water, and as nanocarriers of functional agents for bone-related therapies. The present research demonstrates the possibility of the enlargement of the Brunauer–Emmett–Tel...

This research is focused on preliminary calculations of the thermodynamic model and total Gibbs energy for ceramic coatings based on dicalcium phosphate dihydrate (DCPD, CaHPO4×2H2O) and octacalcium phosphate (OCP, Ca8H2(PO4)6×5H2O) obtained by chemical modification of ceramics based on α-tricalcium phosphate (α-TCP, Ca3(PO4)2). The formation of th...

The structure of hydroxyapatite (HA) plasma coatings obtained by changing the power of the plasma torch (P) from 20 to 26 kW was studied by X-ray diffraction analysis. All coatings contained the decomposition products of hydroxyapatite in the plasma flow, phases of tetracalcium phosphate (TTCP) and CaO. Their number, which increases with increasing...

A comparative study of gelation processes in aqueous solutions of sodium alginate initiated by their chemical crosslinking with divalent ions Ca2+ or Ba2+ was carried out. 3D cryoprinted hydrogel scaffolds of certain architectonics were formed from the studied compositions containing various concentrations of crosslinking agents. It is shown that t...

Gene therapy is one of the most promising approaches in regenerative medicine to restore damaged tissues of various types. However, the ability to control the dose of bioactive molecules in the injection site can be challenging. The combination of genetic constructs, bioresorbable material, and the 3D printing technique can help to overcome these d...

The paper demonstrated the increase of the surface area and meso- and microporosity volume with the low concentration Mg-substitution introduction during the hydroxyapatite (HA) wet method synthesis, as well as samples phase and structure evolution during the heat treatment up to 1200 °C. The incorporation of 0.1 and 1.0 mol.% Mg²⁺ were studied by...

Формативная фабрикация - новый способ производства трехмерных конструкций из неорганических и органических веществ, включая живые клетки, путем их направленной и программируемой сборки в различных физических полях, которые обеспечивают функцию временной и удаляемой бесконтактной поддержки. В качестве физических полей могут выступать магнитные, акус...

Cement materials based on calcium sulfate into which up to 20 mol % of phosphate groups were introduced were obtained in order to improve their cytocompatibility and solubility. It was found that, during exposure of cement materials on the basis of calcium sulfate containing 0, 5, 10, and 20 mol% phosphate groups in model Kokubo solution (simulated...

In the recent years, a magnesium-calcium phosphate materials are considered as an alternative to materials based on the calcium phosphates in the reconstructive surgery. The injectable bone cements have been particular interest for the minimally invasive surgical approaches. The aim of this work is considered to the creating and studying of the str...

Octacalcium phosphate (OCP, Ca8H2(PO4)6·5H2O) is known to be a possible precursor of biological hydroxyapatite formation of organic bone tissue. OCP has higher biocompatibility and osseointegration rate compared to other calcium phosphates. In this work, the synthesis of low-temperature calcium phosphate compounds and substituted forms of those at...

This work is aimed at developing of electrically conductive composite thin films based on calcium phosphates (CP) and multi-walled carbon nanotubes (MWCNT) for bone tissue engineering. A method based on the sputtering of an dispersion of CPs and MWCNTs on a substrate with subsequent exposure to a laser with different power values to form connected...

Changes in the structure and phase composition of the hydroxyapatite (HA) plasma coating were established during deposition at the initial temperatures of 20 and 550°C of the titanium substrate and a depo-sition distance of 95 and 150 mm. The structure of HA coatings was analyzed by SEM and optical microscopy. DSC analysis established the transitio...

Substituted calcium phosphates (CaPs) are vital materials for the treatment of bone diseases and repairing and replacement of defects in human hard tissues. In this paper, we present some applications of the rarely used pulsed electron paramagnetic resonance (EPR) and hyperfine interaction spectroscopy approaches [namely, electron spin-echo envelop...

There is a strong unmet need for bone grafts and substitutes combining osteoinductive capacities and biophysical properties for using them in minimally invasive surgical interventions. We have developed three variants of injectable gene-activated bone substitutes containing three components: octacalcium phosphate microgranules (OCP), plasmid DNA de...

This article presents the results of a study of radiation-induced defects in various synthetic calcium phosphate (CP) powder materials (hydroxyapatite—HA and octacalcium phosphate—OCP) by electron paramagnetic resonance (EPR) spectroscopy at the X, Q, and W-bands (9, 34, 95 GHz for the microwave frequencies, respectively). Currently, CP materials a...

This work is aimed at developing homogeneous, uniformly distributed fine-crystalline coatings based on triclinic octacalcium phosphate pentahydrate (OCP, Ca 8 H 2 (PO 4) 6 ⋅5H 2 O) on the surface of ceramic substrates made of hydroxyapatite (HA, Ca 10 (PO 4) 6 (OH) 2). The process of the crystalline layer of low-temperature calcium phosphates consi...

Two variants of gene-activated hydrogels based on sodium alginate containing plasmid DNA with the gene of vascular endothelial growth factor (VEGF-A) are developed. The former represented alginate hydrogel without additional components; the latter contained up to 25 wt % of octacalcium phosphate (OCP) micrograins. Alginate-based hydrogels without O...